Examples are directed to a fuel injection device positioned in a cylinder liner. In one example, a cylinder includes a combustion chamber which is jointly formed by a piston crown of a piston, by a cylinder barrel which laterally delimits the combustion chamber, and by a cylinder head. The cylinder includes an injection device positioned in the cylinder barrel for direct introduction of fuel into the combustion chamber, which injection device has at least one opening which, during a course of an injection process, is configured to be activated to introduce fuel into the combustion chamber, the injection device terminating flush, at a combustion chamber side, with the cylinder barrel.

A fuel injector includes an injector body with a fuel chamber configured to receive fuel from a fuel line, an injector tip provided at an end of the injector body, and one or more nozzle assemblies provided in the injector tip. The one or more nozzle assemblies have a fuel channel in fluid communication with the fuel chamber, a premixing tube fluidly connected to the fuel channel, and a port fluidly connected to the premixing tube. The premixing tube has an orifice providing an outlet for the injector tip.

Embodiments disclosed herein relate to internal combustion engines, combustion systems that include such internal combustion engines, and controls for controlling operation of the combustion engine. The internal combustion engine may include one or more mechanisms for injecting fuel, air, fuel-air mixture, or combinations thereof directly into one or more cylinders, and controls may operate or direct operation of such mechanisms.

A combustion system is provided for an internal combustion engine including a cylinder head and a piston. In one example, a combustion system may include a cylinder head with a second cylinder surface angled relative to a first cylinder surface, an intake port coupled to the first cylinder surface, an exhaust port coupled to the second cylinder surface, and a piston with a first piston surface parallel to the first cylinder surface and a second piston surface parallel to the second cylinder surface.

A compression ignition (diesel) engine uses two or more fuel charges during a combustion cycle, with the fuel charges having two or more reactivities (e.g., different cetane numbers), in order to control the timing and duration of combustion. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot). At low load and no load (idling) conditions, the aforementioned results are attained by restricting airflow to the combustion chamber during the intake stroke (as by throttling the incoming air at or prior to the combustion chamber's intake port) so that the cylinder air pressure is below ambient pressure at the start of the compression stroke.

An electronic control unit of an internal combustion engine is configured to control the fuel injection valve and to control a spark plug if necessary such that fuel is combusted by pre-mixture compression ignition combustion or flame propagation combustion. The electronic control unit is configured to perform homogeneous combustion in a flame ignition operation range when switching failure has not occurred, the homogeneous combustion being combustion in which fuel homogeneously diffused into the combustion chamber is ignited using the spark plug and is combusted by flame propagation combustion. The electronic control unit is configured to perform spray-guided stratified combustion in a second operation range when the switching failure has occurred, the spray-guided stratified combustion being combustion in which fuel in the fuel injection path is ignited using the spark plug and is combusted by the flame propagation combustion.

An engine is provided, which includes a combustion chamber defined by a piston crown surface, an inner wall surface of a cylinder, and a pentroof ceiling surface formed in a cylinder head, and an ignition part of a spark plug disposed at the ceiling surface to achieve flame propagation combustion inside the combustion chamber. A cavity recessed in a spherical cap shape is formed in a central area of the crown surface. An opening of an intake port is formed in the ceiling surface (intake side) and an opening of an exhaust port is formed in the ceiling surface (exhaust side). When seen in a cross-sectional view taken along a cylinder axis, the ignition part is located above the cavity to be offset toward the exhaust side with respect to a cylinder axial line whereas a cavity center point is located to be offset toward the intake side.

A method for managing the mass of fuel injected into the cylinder of an internal combustion engine fed by direct injection. The pressure and the pressure drop per unit of time are monitored (13) during the starting phase. If the pressure becomes too low (7), or if it drops too quickly (9), the mass of fuel injected on each cycle is adjusted (15) in order to maintain a high fuel pressure in the injector (37). The method can be applied, for example, in the event of low-temperature starting using any type of fuel, for example pure or mixed ethanol.

A gas injector for injecting a gaseous fuel directly into a combustion chamber of an internal combustion engine includes a valve-closing element for releasing and sealing a through opening at a sealing seat; a shielding element, which is situated at an end of the valve-closing element on a side of the combustion chamber and which shields the valve-closing element and the sealing seat with respect to the combustion chamber; and a cooling ring having a first contact area designed for direct contact with the shielding element and a second contact area designed for direct contact with a component of the internal combustion engine, in particular with a cylinder head.

A two-stroke engine piston (1) is disclosed comprising a piston top (3), a mantle surface (5), a stratified scavenging channel (7) in the mantle surface (5), and a weight reduction space (9) arranged between the piston top (3) and the stratified scavenging channel (7). The weight reduction space (9) has a largest first axial extent (a1) at the mantle surface (5) and a second axial extent (a2) radially inside the mantle surface (5), and wherein the second axial extent (a2) is greater than the largest first axial extent (a1). The present disclosure further relates to an engine (30), a hand-held tool (40), and a method of manufacturing an engine piston (1).